大本教への弾圧：二度の事件Oomoto Persecution Marks Prewar Japan Turning Point

In 1892, roughly 25 years after the start of the Meiji era, which marked the dawn of modern Japan, a farmer named Nao Deguchi experienced a divine revelation, recording apocalyptic prophecies. This event became the cornerstone for a new religious movement later structured by her son-in-law, Onisaburo Deguchi (1871–1948). This was the beginning of Oomoto-kyo (大本教).

In 1898, Onisaburo Deguchi undertook spiritual practices and received his own divine revelations. After marrying Nao’s fifth daughter, Sumiko, he became deeply involved in managing the religious organization, establishing two major sacred sites in Ayabe and Kameoka, Kyoto Prefecture, significantly driving its expansion. Onisaburo especially played a crucial role as the second founder-like figure within the movement. He organized and interpreted the divine messages Nao had left behind, further systematizing the teachings by beginning the publication of the extensive mythical scripture known as Reikai Monogatari (『霊界物語』, 81 volumes in total) from 1921. His contributions were considered a major culmination of Japan’s new religious movements that had begun in the late Edo period.

Under Onisaburo’s charismatic religious leadership, Oomoto steadily expanded, experiencing particularly rapid growth amidst the post-World War I turmoil. In the early Taisho period (1912–1926), Oomoto was merely a small regional sect based in Ayabe, Kyoto, with fewer than a thousand followers. However, it gradually expanded its membership, reaching approximately 25,000 followers by around 1919. This year after World War I became a turning point, and according to a contemporary statement by Masazumi Ando, a member of the House of Representatives at the time, the number of followers surged dramatically to “300,000” within just one year. This sudden expansion triggered alarm within government circles and became one of the primary reasons behind the subsequent intense religious persecution that would significantly impact Japanese society leading up to World War II.

Viewing the rapidly growing Oomoto as a potential threat, early on the morning of February 12, 1921, the government mobilized approximately 200 police officers to raid Oomoto’s headquarters in Ayabe, Kyoto Prefecture. Onisaburo Deguchi and other key members were arrested on charges including insulting the Emperor and the imperial institution—a crime known in Japan as fukeizai (不敬罪), the crime of disrespect. The police searched vigorously based on unfounded rumors, such as “hiding explosives” and “burying people alive,” but ultimately failed to find evidence supporting their suspicion of a conspiracy aiming to overthrow the state. Nevertheless, the authorities partially destroyed the shrine at the headquarters and forcibly remodeled the tomb of Nao Deguchi, the sect’s founder. Known today as the “First Oomoto Incident” (第一次大本事件), this event led to Oomoto being publicly vilified as a “heretical sect,” severely damaging its social reputation nationwide.

The sentencing of leader Onisaburo Deguchi to a suspended prison term temporarily halted the previously thriving propagation activities. Fortunately, the religious group itself avoided complete destruction, but it experienced a drastic shift in direction and the departure of key leaders. I personally perceive this around-1921 period as marking Oomoto’s transformation into an entirely different organization—this was a pivotal turning point. Following this incident, Oomoto publicly renamed itself Kodo Omoto (皇道大本), outwardly emphasizing reverence toward the imperial family, which could also be interpreted as an attempt by Onisaburo to publicly demonstrate conformity toward the government authorities who had harshly suppressed the group. This leadership approach, which can be viewed as conformist to authority, led to the departure of dedicated followers and resulted in the hollowing out of the organization. One characteristic feature of the Taisho era was precisely such reactionary sentiments against conforming to the establishment.

Nevertheless, despite its internal loss of vitality, Onisaburo continued his efforts to expand propagation activities, and by the late 1920s, the religious organization regained its momentum. However, this subsequent expansion had a significantly altered vision, now aiming at international outreach, marking a period in which Oomoto essentially began to lose its original identity and entered a phase of confusion. For example, to dispel its negative social image and pursue activities on a global scale, Oomoto began actively engaging in various social initiatives, such as adopting Esperanto as an international language, conducting overseas missionary work in places like China and Tibet, and becoming involved in international peace movements.

In particular, after the Great Kanto Earthquake of 1923, a pivotal turning point leading toward World War II, Oomoto began actively collaborating with China’s Komanjikai (紅卍字会), aiming to further internationalize its missionary activities through strengthened cooperation. However, by the end of 1926, the era shifted dramatically from the reactionary Taisho period (1912–1926), characterized by responses against Meiji-era modernization, to the Showa period (from 1926), marked by rapidly intensifying militarism. During this era, as governmental control over citizens intensified, state surveillance and suppression of free speech became routine, while the influence of the military (particularly the Army) grew politically overwhelming, even powerful enough to influence the Emperor himself. Consequently, under the Army’s influence, government authorities perceived Oomoto as outwardly conforming to militarism by proclaiming reverence for the imperial family, yet secretly aiming to abolish the imperial system to establish Onisaburo Deguchi as a dictatorial leader. Thus, Oomoto was increasingly regarded as a dangerous organization plotting to change Japan’s state structure fundamentally.

Notably, the Special Higher Police (特別高等警察), effectively operating under the protection of the Army, no longer viewed Oomoto merely as a “disrespectful new religion,” as it once had. Instead, by the Showa period, it treated Oomoto explicitly as an anti-establishment social movement actively opposing the political system, and thus subject to severe crackdowns. Under such tense suspicion between the growing religious organization of Oomoto and the militaristic authorities, on the early morning of December 8, 1935, approximately 500 armed police simultaneously raided Oomoto’s headquarters in Ayabe and Kameoka, arresting Onisaburo Deguchi and numerous senior leaders and believers on charges of violating the Peace Preservation Law (治安維持法) and insulting the Emperor (不敬罪). This event became known as the “Second Oomoto Incident” (第二次大本事件).

Compared to the “First Oomoto Incident,” when the military’s power was still limited, this second incident occurred at a time when the military’s authority had become absolute, resulting in far more comprehensive and devastating persecution. Around 3,000 followers nationwide were arrested and interrogated, and all of the sect’s facilities were completely demolished by dynamite. Furthermore, authorities went so far as to exhume and desecrate the mausoleum and tomb of the sect’s founder, attempting to psychologically destroy believers’ faith. The sheer thoroughness of this suppression profoundly shook society and became a crucial turning point in Japan’s march toward World War II.

At the time, interrogations conducted by the already out-of-control military authorities regularly involved torture, resulting in the mysterious deaths of 16 followers and effectively paralyzing the religious organization’s functioning. The government immediately banned all Oomoto scriptures and writings, thoroughly suppressing its religious activities both physically and mentally. Furthermore, as the mass media had become subservient to the military, newspapers daily published sensationalist articles vilifying Oomoto as a “national traitor” (国賊) and a “heretical cult” (邪教). False rumors, such as allegations of secretly stockpiling weapons or plotting rebellions—fabricated by authorities—were widely disseminated to the public through newspapers and magazines. This dark legacy resulting from the military’s extreme actions is one key reason why contemporary Japanese still hold a deeply rooted aversion to religion today. Such was the profound impact of this historical memory.

As a result, Oomoto effectively collapsed, and Onisaburo Deguchi himself endured a long imprisonment awaiting trial. Due to this second persecution, many followers lost their place of worship and dispersed. Some moved to other religious groups, while others sought to establish new movements inspired by Oomoto’s teachings. But was Oomoto’s decline solely due to the military’s radical actions? To truly understand this critical question, we must examine a key individual. In the next article, we will further explore this aspect.